Paypal 沙箱错误：请求已中止：无法创建 SSL/TLS 安全通道

Question

如果是沙箱，我会收到错误 "The request was aborted: Could not create SSL/TLS secure channel." 但这适用于我的实时凭据。

这是代码片段

            var uri = new Uri(url);
            ServicePointManager.SecurityProtocol = SecurityProtocolType.Tls12;
            var request = WebRequest.Create(uri);
            var encoding = new UTF8Encoding();
            var requestData = encoding.GetBytes(postData);

            request.ContentType = "application/x-www-form-urlencoded";
            request.Method = "POST";
            request.Timeout = (300 * 1000); //TODO: Move timeout to config
            request.ContentLength = requestData.Length;

            using (var stream = request.GetRequestStream())
            {
                stream.Write(requestData, 0, requestData.Length);
            }

            var response = request.GetResponse();

            string result;

            using (var reader = new StreamReader(response.GetResponseStream(), Encoding.ASCII))
            {
                result = reader.ReadToEnd();
            }

            return result;

Answer 1

问题是 C# 在尝试连接到 PayPal 服务器时默认使用 SSL3，而 PayPal 不接受。 PayPal 至少需要（更安全的）TLS 1.2。

您可以通过以下代码进行设置：

ServicePointManager.SecurityProtocol = SecurityProtocolType.Tls12;